The present invention relates to plate-fin heat exchangers, for example, for use in aftercoolers, radiators and gas coolers.
The term "aluminum" as used herein includes pure aluminum and aluminum alloys.
Generally with heat exchangers for use in aftercoolers, radiators and the like, improved performance can be achieved more effectively by providing an increased heat transfer area than by disturbing the flow of the fluid, especially remarkable in the case of air, in view of the characteristics of the fluid.
Such heat exchangers heretofore known have at least one first fluid channel for passing a first fluid therethrough and at least one second fluid channel for passing therethrough the second fluid to be subjected to heat exchange with the first fluid. The first channel is defined by two flat plates opposed to each other at a specified spacing, and a first channel forming member provided between these plates. The channel forming member is made of an aluminum extrudate which comprises a pair of opposed spacing side walls, and a connecting wall resembling comb teeth in cross section and interconnecting the side walls. Since the channel forming member comprises the comb-toothed connecting wall having thin fins, the member is not extrudable satisfactorily, is extremely difficult to make and is likely to involve dimensional variations. The ends of the fins are liable to become rounded when extruded and therefore contact the flat plate over a reduced area and be prone to forming a faulty joint. The channel forming member has relatively low strength, so that the platelike base portion is liable to fracture or the fin is liable to bend during handling. The member is therefore difficult to handle. Consequently, the heat exchanger is not easy to fabricate, has a relatively small heat transfer area and is low in heat exchange efficiency.